PHPのエクステンションなどをインストールしたときにちゃんとロードされているか確認したい時に便利なオプション –ini
$ php --ini
Configuration File (php.ini) Path: /etc/php/8.1/cli
Loaded Configuration File: /etc/php/8.1/cli/php.ini
Scan for additional .ini files in: /etc/php/8.1/cli/conf.d
Additional .ini files parsed: /etc/php/8.1/cli/conf.d/10-opcache.ini,
/etc/php/8.1/cli/conf.d/10-pdo.ini,
/etc/php/8.1/cli/conf.d/15-xml.ini,
/etc/php/8.1/cli/conf.d/20-calendar.ini,
/etc/php/8.1/cli/conf.d/20-ctype.ini,
/etc/php/8.1/cli/conf.d/20-dom.ini,
/etc/php/8.1/cli/conf.d/20-exif.ini,
/etc/php/8.1/cli/conf.d/20-ffi.ini,
/etc/php/8.1/cli/conf.d/20-fileinfo.ini,
/etc/php/8.1/cli/conf.d/20-ftp.ini,
/etc/php/8.1/cli/conf.d/20-gettext.ini,
/etc/php/8.1/cli/conf.d/20-iconv.ini,
/etc/php/8.1/cli/conf.d/20-phar.ini,
/etc/php/8.1/cli/conf.d/20-posix.ini,
/etc/php/8.1/cli/conf.d/20-readline.ini,
/etc/php/8.1/cli/conf.d/20-shmop.ini,
/etc/php/8.1/cli/conf.d/20-simplexml.ini,
/etc/php/8.1/cli/conf.d/20-sockets.ini,
/etc/php/8.1/cli/conf.d/20-sysvmsg.ini,
/etc/php/8.1/cli/conf.d/20-sysvsem.ini,
/etc/php/8.1/cli/conf.d/20-sysvshm.ini,
/etc/php/8.1/cli/conf.d/20-tokenizer.ini,
/etc/php/8.1/cli/conf.d/20-xmlreader.ini,
/etc/php/8.1/cli/conf.d/20-xmlwriter.ini,
/etc/php/8.1/cli/conf.d/20-xsl.iniモジュールがロードされているかどうかであれば -m オプションでもよい
$ php -m
[PHP Modules]
calendar
Core
ctype
date
dom
exif
FFI
fileinfo
filter
ftp
gettext
hash
iconv
json
libxml
openssl
pcntl
pcre
PDO
Phar
posix
readline
Reflection
session
shmop
SimpleXML
sockets
sodium
SPL
standard
sysvmsg
sysvsem
sysvshm
tokenizer
xml
xmlreader
xmlwriter
xsl
Zend OPcache
zlib
[Zend Modules]
Zend OPcache